Limited Scientific Information Available to Support Conclusions in Draft Environmental Impact Statement for Drakes Bay Oyster Company

WASHINGTON — A new report from the National Research Council finds that most of the conclusions presented in the National Park Service's draft Environmental Impact Statement (EIS) for the Drakes Bay Oyster Company at Point Reyes National Seashore in California, although reasonable, lack strong scientific support due to the limited amount of available data.Furthermore, the limited information that assesses the effects of the company's operations on the resources of Drakes Estero could also support other conclusions, some of which could indicate a lower level of environmental impact.The report adds that the draft EIS needs to better define the criteria used to assess possible environmental impacts.

"There is little scientific literature on Drakes Estero, and research on the potential impacts that oyster farming has on this particular ecosystem is even sparser," said Thomas Malone, chair of the committee that wrote the report andprofessor emeritus at the University of Maryland Center for Environmental Science."Trying to assess environmental impacts based on a limited amount of information would be similar, for example, to estimating rainfall for an entire year when rainfall records are only available for March.The draft EIS could have done a better job discussing how this limited data on Drakes Estero results in less definitive scientific conclusions."

The Research Council report assesses the scientific information, analyses, and conclusions in the draft EIS for Drakes Bay Oyster Company Special Use Permit, which will be used to determine the potential environmental impacts of a proposed 10-year permit extension of the company's operations. The statement examines the effects of the oyster farming operations and facilities in Drakes Estero under four scenarios: termination of the permit and removal of the oyster farm, the farm's current operating conditions, operating conditions specified in the farm's 2008 permit, and expanded operations with new facilities and higher production levels.For each scenario, the draft EIS presents assessments of the oyster farm's potential impacts on 12 resource categories -- such as wetlands, wildlife and wildlife habitat, special-status species, and water quality -- and classifies the impacts as beneficial or adverse.

Due to the limited data on Drakes Estero, the National Park Service relied mainly on inferences from research conducted in other locales, as this was the only approach that could be used under the circumstances.However, this approach resulted in moderate to high levels of uncertainty for seven of the eight resource categories reviewed by the committee.In addition, not enough information was available to establish how the oyster farm's operation could impact the various categories; thus, this same information could be interpreted as leading to other possible, alternate conclusions that were not discussed in the EIS.The committee determined that for resource categories assigned a moderate or high level of uncertainty -- such as harbor seals, soundscape, and water quality -- the impacts could also be lower than those presented in the draft EIS.

The committee also evaluated the Atkins peer review of the EIS, which was commissioned by the Park Service.The selected experts were well-qualified, and their comments were mostly consistent with the committee's findings.However, the Atkins peer review needs additional expertise to cover the range of scientific topics in the EIS.In addition, it does not include a review of the definitions of impact intensity.

The report was sponsored by the National Park Service.The National Academy of Sciences, National Academy of Engineering, Institute of Medicine, and National Research Council make up the National Academies.They are independent, nonprofit institutions that provide science, technology, and health policy advice under an 1863 congressional charter.Panel members, who serve pro bono as volunteers, are chosen by the Academies for each study based on their expertise and experience and must satisfy the Academies' conflict-of-interest standards.The resulting consensus reports undergo external peer review before completion.For more information, visit http://national-academies.org/studycommitteprocess.pdf.A committee roster follows.